Positive relief forming of polycrystalline diamond structures and resulting cutting tools

ABSTRACT

Embodiments of the invention relate to methods of making articles having portions of polycrystalline diamond bonded to a surface of a substrate and polycrystalline diamond compacts made using the same. In an embodiment, a molding technique is disclosed for forming cutting tools comprising polycrystalline diamond portions bonded to the outer surface of a substrate.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.15/359,019 filed Nov. 22, 2016, which is a division of U.S. applicationSer. No. 14/463,587 filed on 19 Aug. 2014, the disclosure of each ofwhich is incorporated herein, in its entirety, by this reference.

BACKGROUND

Wear resistant polycrystalline diamond (“PCD”) materials are utilized ina variety of mechanical applications. For example, PCD materials areused in drilling tools (e.g., cutting elements, gage trimmers, etc.),machining equipment, bearing apparatuses, wire-drawing machinery,cutting tools (e.g., endmills, drills, etc.), and in other mechanicalapparatuses.

PCD material has found particular utility in superabrasive cuttingelements such as rotary drill bits, endmills, and drills. Apolycrystalline diamond compact (“PDC”) such as those used in rotarydrill bits includes a PCD layer commonly known as the PCD body or table.The PCD body is formed and bonded to a substrate using ahigh-pressure/high-temperature (“HPHT”) process.

Conventional PDCs are normally fabricated by placing a cemented carbidesubstrate into a container or cartridge with a volume of diamondparticles positioned on an upper surface of the cemented carbidesubstrate. A number of such cartridges may be loaded into an HPHT press.The substrate(s) and volume of diamond particles are then processedunder HPHT conditions in the presence of a catalyst material that causesthe diamond particles to bond to one another to form a matrix of bondeddiamond grains defining a PCD body or table. The catalyst material isoften a metal-solvent catalyst (e.g., cobalt, nickel, iron, or alloysthereof) that is used for promoting intergrowth of the diamondparticles.

In one conventional approach, a constituent of the cemented carbidesubstrate, such as cobalt from a cobalt-cemented tungsten carbidesubstrate, liquefies and sweeps from a region adjacent to the volume ofdiamond particles into interstitial regions between the diamondparticles during the HPHT process. The cobalt acts as a metal-solventcatalyst to promote intergrowth between the diamond particles, whichresults in the formation of a matrix of bonded diamond grains havingdiamond-to-diamond bonding therebetween, with interstitial regionsbetween the bonded diamond grains being occupied by the metal-solventcatalyst.

Traditional methods of making milling tools such as drills and endmillshaving a PCD portion thereon have typically included forming slots insubstrate, forming a PCD body in the slot in a substrate and removingthe substrate back to expose the PCD body. However, such methods canresult in cracking and delamination of the PCD body due to mismatches inthe coefficients of thermal expansion (“CTE”) between the substratematerial and the PCD body.

Despite the availability of a number of different types of PCD cuttingtools, manufacturers and users of PCD cutting tools continue to seekimproved PCD cutting tools.

SUMMARY

Embodiments of the invention relate to methods of making PCD structureshaving one or more PCD portions bonded to a substrate and PCD cuttingtools made using the same. In an embodiment, a PCD structure may be madeby forming a mold assembly including a mold having a cavity including atleast one flute recess therein, a substrate positioned within thecavity, and a plurality of diamond particles positioned within the atleast one flute recess. The method further includes subjecting the moldassembly to an HPHT process effective to sinter the diamond particlesand bond at least one PCD portion at least partially formed from thediamond particles to an imperforate portion of the substrate (e.g., atan outer surface of the substrate).

In an embodiment, a method of making a PCD structure includes providinga substrate having a surface, and positioning at least one diamondmaterial flute volume including diamond particles therein around aportion of the surface of the substrate. The method further includessubjecting the substrate having the at least one diamond material flutevolume positioned therearound to HPHT conditions effective to sinter thediamond particles and bond at least one PCD portion at least partiallyformed from the diamond particles to the substrate (e.g., at an outersurface of the substrate).

In an embodiment, a method of making a PDC includes making a mold havinga cavity including a PCD body recess and at least one standing featurerecess extending from the PCD body recess. The method further includespositioning diamond particles in the PCD body recess, a substrate in thecavity, and diamond particles in the at least one standing featurerecess. The method additionally includes enclosing the mold having thecontents therein in a pressure transmitting medium. The method alsoincludes subjecting the mold having the contents to HPHT conditionseffective to sinter the diamond particles and bond PCD portions at leastpartially formed from the diamond particles to the substrate.

Features from any of the disclosed embodiments may be used incombination with one another, without limitation. In addition, otherfeatures and advantages of the present disclosure will become apparentto those of ordinary skill in the art through consideration of thefollowing detailed description and the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings illustrate several embodiments of the invention, whereinidentical reference numerals refer to identical or similar elements orfeatures in different views or embodiments shown in the drawings.

FIG. 1 is an isometric view of a cutting tool according to anembodiment.

FIG. 2A is an isometric view of an endmill according to an embodiment.

FIG. 2B is an isometric view of a face cutting endmill according to anembodiment.

FIG. 2C is a top elevation view of the face cutting endmill depicted inFIG. 2B.

FIG. 3 is an isometric view of a tap according to an embodiment.

FIGS. 4A-4D are isometric views of PDCs according to embodiments.

FIGS. 5A-5C are isometric views of PDCs having additional PCD portionsthereon according to embodiments.

FIG. 5D is a partial isometric view of a bit body having the PDC shownin FIG. 5C attached thereto according to an embodiment.

FIG. 6A is an isometric view of a mold according to an embodiment.

FIG. 6B is an isometric view of a substrate being inserted into the moldof FIG. 6A.

FIG. 6C is an isometric view of a substrate disposed in the mold of FIG.6A.

FIG. 6D is an isometric view of a mold assembly including the substrateand diamond particles disposed in the mold of FIG. 6A.

FIG. 6E is an isometric view of a cutting tool formed using the moldassembly of FIG. 6D according to an embodiment.

FIG. 6F is an isometric view of a substrate being inserted into the moldaccording to an embodiment.

FIG. 6G is an isometric view of the substrate disposed in the mold ofFIG. 6F.

FIG. 6H is an isometric view of a cutting tool formed using the moldassembly of FIG. 6G.

FIG. 7A is an isometric cutaway view of a mold having a substrateinserted therein according to an embodiment.

FIG. 7B is a top elevation view of the mold of FIG. 7A.

FIG. 7C is an isometric view of a mold assembly including the substrateand mold from FIG. 7A.

FIG. 7D is an isometric view of a cutting tool formed using the moldassembly of FIG. 7C.

FIG. 8A is an isometric view of a substrate having at least one diamondmaterial tube wrapped around a surface thereof, according to anembodiment.

FIG. 8B is an isometric cutaway view of the at least one diamondmaterial tube used to wrap around the substrate in FIG. 8A, according toan embodiment.

FIG. 8C is a top elevation view of the tube of FIG. 8B.

FIG. 8D is an isometric view of a mold assembly containing a substratehaving at least one tube wrapped around a surface thereof, according toan embodiment.

FIG. 8E is an isometric view of a cutting tool formed using the moldassembly of FIG. 8D according to an embodiment.

FIG. 8F is a mold having tubes packed in the recesses therein and usedfor forming PCD structures according to an embodiment.

FIG. 8G is a top elevation view of a mold assembly using the mold ofFIG. 8D or 8G.

FIG. 9 is an isometric view of a mold according to an embodiment.

FIG. 10A is an isometric view of a mold according to an embodiment.

FIG. 10B is an isometric view of a PDC made using the mold of FIG. 10Aaccording to an embodiment.

FIG. 10C is an isometric view of a mold according to an embodiment.

FIG. 11A is an isometric view of an embodiment of a rotary drill bit.

FIG. 11B is a top elevation view of the rotary drill bit shown in FIG.11A.

DETAILED DESCRIPTION

Embodiments of the invention relate to PCD structures and methods offorming PCD structures by bonding one or more PCD portions to asubstrate. In particular, the methods further include using moldingtechniques to facilitate bonding of the one or more PCD portions to thesubstrate.

FIGS. 1-3 illustrate embodiments of cutting tools containing one or morePCD portions. The cutting tools may include a substrate having asurface, an end surface, and one or more PCD portions attached to thesubstrate. The substrate may comprise a carbide material, such as acemented carbide material (e.g., cobalt-cemented tungsten-carbide). Thesubstrate may include, without limitation, cemented carbides, such astungsten carbide, titanium carbide, chromium carbide, niobium carbide,tantalum carbide, vanadium carbide, or combinations thereof cementedwith iron, nickel, cobalt, or alloys thereof, along with cementingconstituents such as cobalt, nickel, iron or alloys thereof. Forexample, in an embodiment, the substrate 102 comprises cobalt-cementedtungsten carbide. In embodiments, a carbide substrate may include aninfiltrant material such as copper, aluminum, or silicon.

The one or more PCD portions may include a plurality of polycrystallinediamond grains exhibiting diamond-to-diamond bonding therebetween (e.g.,sp³ bonding) and having interstitial spaces or regions therebetween. Atleast a portion of the plurality of interstitial regions, or in someembodiments, substantially of the interstitial spaces may be occupied bya metal-solvent catalyst, such as iron, nickel, cobalt, or mixtures oralloys of thereof. The one or more PCD portions may exhibit an averagediamond grain size of about 50 μm or less, such as about 30 μm or lessor about 20 μm or less. For example, the average grain size of thediamond grains may be about 1 μm to about 60 μm and, in someembodiments, about 5 μm to about 30 μm, about 10 μm to about 20 μm. Insome embodiments, the average grain size of the diamond grains may beabout 60 μm or less, such as about 2 μm to about 50 μm, about 10 μm toabout 30 μm, about 2 μm to about 5 μm or submicron. The as-sintereddiamond grain size may differ from the average particle size of thediamond particles prior to sintering due to a variety of differentphysical processes, such as grain growth, diamond particles fracturing,addition of carbon provided from another carbon source (e.g., dissolvedcarbon in the metal-solvent catalyst), or combinations of the foregoing.

Typically, PCD is formed when a plurality or mass of diamond particles(i.e., diamond powder) is subjected to HPHT conditions effective tosinter the diamond particles. The presence of a catalyst material aidsin diamond-to-diamond bond formation between the diamond particles toform a matrix of bonded diamond grains exhibiting diamond-to-diamondbonding therebetween. An assembly including diamond particles, asubstrate, and a catalyst material may be loaded into a refractory metalcontainer (e.g., a refractory metal can) which may be loaded into apressure transmitting medium (e.g., pyrophyllite), placed into an HPHTpress, and subjected to HPHT conditions effective to sinter the diamondparticles together to form PCD.

Diamond particles may be provided in the form of a diamond powder. Asuitable diamond powder may comprise one or more modes (e.g., bimodal,or trimodal or greater) of average diamond particle sizes therein. Byway of non-limiting example, a suitable bimodal diamond powder mayinclude a first average diamond particle size of about 10 μm or greater(e.g., 10 μm to about 50 μm, about 15 μm to about 40 μm, about 20 μm toabout 30 μm, about 15 μm, about 18 μm, about 20 μm, about 25 μm, orabout 30 μm) and a second average diamond particle size of about 1 μm toabout 20 μm (e.g., about 2 μm to about 15 μm, about 4 μm to about 10 μm,about 2 μm, about 5 μm, about 10 μm, or about 15 μm). Further, smalleraverage particle size distributions are contemplated herein. Forexample, a multimodal diamond powder may include any of the aboveaverage diamond particle size distributions in a mode and include a modeexhibiting an average diamond particle size distribution of less thanabout 1 μm, such as, about 1 nm to about 500 nm, about 10 nm to about250 nm, about 20 nm to about 100 nm, about 5 nm, about 10 nm, about 20nm, about 50 nm, about 100 nm, about 250 nm, or about 500 nm. In anembodiment, any one of the average diamond particle sizes recited hereinmay be used in combination with another average diamond particle size tocreate a multimodal diamond powder (e.g., where the average diamondparticle sizes differ from each other).

In some embodiments, the HPHT sintering process may be carried out withdiamond material (e.g., diamond powder) in the presence of ametal-solvent catalyst (e.g., iron, cobalt, nickel, or alloys of theforegoing), which may be provided in the form of one or more of apowder, a foil or disc, or from a substrate to which the one or more PCDportions are to be bonded, which at least partially melts and sweepsinto the spaces between diamond particles at high temperatures tofacilitate diamond-to-diamond bonding. Pressure transmitting mediumsand/or structures may include by way of non-limiting example arefractory metal can, graphite structure, pyrophyllite, or any othermaterials known in the art. For example, suitable pressure transmittingmediums and/or structures are described in U.S. Pat. Nos. 6,338,754;7,866,418; 8,074,566; and 8,323,367; each of which is incorporatedherein, in its entirety, by this reference.

In embodiments, suitable pressures for the HPHT sintering process mayinclude pressures of about 5 GPa or greater, such as, about 5 GPa toabout 15 GPa, about 6 GPa to about 10 GPa, about 7 GPa to about 9 GPa,about 7 GPa and greater, about 5 GPa, about 6 GPa, about 7 GPa, or about7.5 GPa. In embodiments, suitable temperatures for the HPHT sinteringprocess may include temperatures at which diamond is stable. Forexample, diamond-stable temperatures used in an HPHT sintering processmay include a temperature of at least about 1000° C., such as about1100° C. to about 2200° C., about 1200° C. to about 1800° C., about1300° C. to about 1600° C., about 1200° C., about 1300° C., about 1400°C., about 1500° C., about 1200° C. or greater, or about 1400° C. orgreater.

Referring to FIG. 1, in an embodiment, a cutting tool 100 may beconfigured as a drill. The cutting tool 100 includes a substrate 102(e.g., tool shaft or shank) having PCD portions 110 bonded to orotherwise attached to the substrate 102. As shown in FIG. 1, the PCDportions 110 may be bonded directly to an end surface 104 a of thesubstrate 102 and extend a height or standoff distance S therefrom. Inan embodiment (not shown), the PCD portions 110 may be bonded directlyto the surface 104 (e.g., a peripheral or lateral surface) of thesubstrate 102 and extend a height or standoff distance S therefrom.Traditional spade drills employ a cutting insert positioned within acavity formed on the end of a cylindrical substrate. The cutting tool100 (i.e., drill) shown in FIG. 1 eliminates the need to form one ormore cavities or recesses in a substrate by having the PCD portions 110forming the cutting edge thereof bonded directly onto a surface of asubstrate (e.g., at a conical end or end surface 104 a of a drill).While the cutting tool 100 is depicted with two PCD portions 110defining two cutting faces, one or more PCD portions defining one ormore cutting faces may be used, such as by way of non-limiting examplethree PCD portions 110, or four PCD portions 110. The PCD portions 110may align (e.g., extend generally parallel to) or otherwise associatewith debris slots (not depicted) formed in the substrate 102 tofacilitate material removal during drilling operations. As discussed inmore detail below, in an embodiment, a substrate having debris slotshelically formed therein may be aligned with the PCD portions 110 by afeature thereon to allow for formation of a cutting tool having debrisslots aligned with the PCD portions 110.

Referring to FIG. 2A-2C, in embodiments, a cutting tool 200 a or 200 bmay be configured as an endmill having PCD portions 210 bonded to asubstrate 202 at a surface 204 and/or end surface 204 a thereof. Asshown in FIG. 2A-2C, the PCD portions 210 may extend generally helicallyaround the surface 204 and optionally extend onto or otherwise bedisposed on the end surface 204 a thereof. The PCD portions 210 mayextend away from the substrate 202 a width or standoff distance S. ThePCD portions 210 extending generally helically around the substrate 202define flutes or cutting faces of the cutting tool 200 a or 200 b. Thecutting tool 200 a or 200 b may have one or more PCD portions 210 (e.g.,flutes, and/or cutting faces) extending generally helically around thesubstrate 202, such as but not limited to two PCD portions 210, threePCD portions 210, or four PCD portions 210. In embodiments, such asshown in FIG. 2B, a generally helically extending (or radiallyextending) PCD portion 210 may also extend from the surface 204 togenerally a center of the end surface 204 a disposed at an end of thesubstrate 202. Traditional milling tools formed using PCD and asubstrate require a channel or recess formed in substrate into which adiamond powder is inserted. The tools and methods for making toolsdescribed herein eliminate the need to insert diamond powders into arecessed substrate. In addition, such a configuration may impart adesirable compressive residual stress state to the one or more PCDportions 210.

FIG. 2C is a top view of the cutting tool 200 b shown in FIG. 2B. ThePCD portions 210 may extend across and be bonded directly to at least aportion of an end surface 204 a. While the cutting tools 200 a and 200 bare shown having a flat end surface 204 a, other shapes for end surfacesmay be used, such as at least one of a domed end surface, a chamfered orfilleted end surface, a stepped end surface, or any other suitablegeometric configuration. The differing end surfaces may define aball-nose tool, a radiused tool, a step tool, or another type of cuttingtool.

Generally, embodiments disclosed herein may include threading taps orthreading dies. Referring to FIG. 3, in an embodiment, a cutting tool300 may be configured as a threading tap having PCD portions 310including a plurality of thread cutting bodies 311 thereon, bonded to asubstrate 302 (e.g., shaft or shank) at a surface 304 thereof. The PCDportions 310 may be aligned generally helically around or verticallywith the substrate 302, and the plurality of thread cutting bodies 311may be positioned, or formed on the PCD portions 310 such that theplurality of thread cutting bodies 311 is substantially perpendicular toa longitudinal axis L of the substrate 302 or oriented at anotherselected angle.

In an embodiment, the cutting elements 100, 200 a or 200 b, or 300 mayhave a substrate 102, 202, or 302 exhibiting any selected diameter orother lateral dimension, such as by way of non-limiting example, about500 μm or more, about 1 mm to about 5 cm, about 5 mm to about 3 cm,about 1 cm to about 2 cm, or about 1/32 or more, about 1/16 of an inchto about 2 inches, about ⅛ of an inch to about 1 inch, about ¼ of aninch to about ¾ of an inch, about ½ inch, or about ⅓ of an inch.

In embodiments, the cutting tool 200 b depicted in FIG. 2C, thesubstrate 102, 202, or 302 of the cutting element or PCD structure 100,200 a or b, or 300 may include a diameter Ds selected to exhibit adesired total diameter Dt of the cutting tool 100, 200 a or b, or 300when the PCD portions 110, 210, or 310 are bonded thereto. A standoffthickness S of the PCD portions 110, 210, or 310 may be selected toimpart a selected dimensional characteristic (e.g., total diameter) tothe cutting tool 100, 200 a or b, or 300 when bonded to the substrate102, 202, 302. In embodiments, the standoff distance S may be about 250μm or more, such as, about 250 μm to about 3 cm, about 500 μm to about 2cm, about 500 μm to about 1 cm, about 1 mm to about 50 mm, about 2 mm toabout 10 mm, about 500 μm to about 5 mm, about 500 μm, about 1 mm, about3 mm, about 10 mm, or about 1 cm. In embodiments, and as shown in FIG.2C, the PCD portions 110, 210, or 310 may exhibit a width W, as measuredlaterally from one side of the PCD portion 110, 210, or 310 to the otherside of the same PCD portion 110, 210, or 310 (e.g. as measuredcircumferentially about the surface). Suitable widths W may be selectedbased upon, among other considerations, desired debris clearance,bonding area between the PCD body and the substrate, shape of the PCDportion, total area of PCD material used, diameter of the substrate,total diameter of the tool, or combinations of the foregoing. Suitablewidths W may be about 250 μm or more, about 250 μm to about 3 cm, about500 μm to about 1 cm, about 1 mm to about 50 mm, about 2 mm to about 10mm, about 500 μm to about 5 mm, about 500 μm, about 1 mm, about 3 mm,about 10 mm, or about 1 cm. In embodiments, the PCD portions 110, 210,or 310 may form a cutting face having an angle θ with respect to thesurfaces 104, 204, 204 a, or 304 at the point of attachment of the PCDportion. The angle θ may be about 90 degrees or less, such as about 90degrees to about 30 degrees, about 80 degrees to about 45 degrees, about75 degrees to about 60 degrees, about 90 degrees, about 75 degrees,about 60 degrees, or about 45 degrees.

As previously discussed, the substrate may include any materialsufficient to bond with PCD material to form a PCD structure (e.g., aPDC). For example, the substrate 102, 202, or 302 may include a cementedcarbide material made from any of the substrate materials describedherein, such as cobalt-cemented tungsten carbide. The PCD portions 110,210, or 310 may also be formed from any of the diamond particles (e.g.,diamond powders) including any average particle size distributionsand/or modes, and any catalyst or infiltrant materials described hereinwith respect to a PCD body.

Cutting tools having PCD portions (e.g., cutting faces, flutes, etc.)thereon are traditionally formed by forming recesses into a substrate,inserting diamond powder into the substrate, sintering the diamondpowder to form PCD and bonding the PCD to the interior surface of therecess in the substrate, and then removing the substrate material toform flutes and/or expose the PCD material. The above method is timeconsuming, expensive, and can result in delamination of the PCD body inthe recess unless large amounts of cobalt or another catalyst materialare present within the PCD body which can result in decreased wearresistance and thermal stability of the PCD body. Further, a commonproblem of elongated substrates having a PCD body formed within a recessalong the length thereof, is cracking in the PCD due to mismatch ofthermal expansion between the PCD material and the substrate material towhich it is bonded and/or cooling variation. In addition, the PCDmaterial is compressed in the recess at high temperatures and highpressures and is then bonded to the recess upon cooling, which canresult in cracking from the tensile stresses exerted from the recess inthe substrate. The cutting tools formed by the methods described hereinmay reduce cracking and/or tensile stress states as compared to thetensile stress states exhibited by cutters made by cutting a recess intoa substrate and then forming a PCD body therein. The geometry of the PCDportions and the substrates may be selected so that residual stresses inthe PCD portions are sufficient to provide a damage tolerant PCDportions. The substrates describe herein may have a bonding surface towhich the PCD portions are bonded that are un-recessed or imperforate,or put another way, may be formed without a recess for bonding PCDtherein.

Referring to FIGS. 4A-4D, in embodiments, a PDC cutting tool (e.g., aPCD structure) may be configured with a PCD body positioned on top of asubstrate. Such as PCD body may include a feature standing off of thePCD body and/or substrate. For example, such as a feature standing offof the substrate may be formed from a mold. The PCD body may be formedin a manner resulting in the PCD body having a geometry (e.g., lateralshape and/or size) different than that of the substrate. PCD bodies andsubstrates, as described with respect FIGS. 4A-4D may be formed usingany of the PCD materials, substrate materials, and methods for formingPCDs or PDCs disclosed herein, including but not limited to diamondpowder compositions, carbide compositions, sintering process conditions,and combinations of the foregoing. PCD bodies according to embodimentsdepicted in FIGS. 4A-4D may be formed using molds (e.g., cans,refractory cans, etc.) having a preformed negative shape of the finishedPCD body therein rather than forming the PCD body and machining orotherwise processing the PCD body to a final finished shape anddimension. For example, the mold may include a cavity having a firstportion including a shape complementary to the substrate (describedgenerically as the cavity herein) and one or more second portions thatmay include a flute recess extending around a portion of or surface ofthe first portion. In embodiments, the cavity may include a thirdportion or more portions, without limitation. The second portion and/orthird portion may comprise the flute recess, a PCD body cavity, or astanding feature cavity as described herein. While embodiments describedbelow use specific terms for the cavity portions, portions of thecavities described below may be characterized as the first portion, thesecond portion, or the third portion.

Referring to FIG. 4A, in embodiments, a PDC 400 a may include asubstrate 402, a PCD body 406 a including a working surface 414 a, abonding surface 415 a bonded to the substrate 402 having a lateralsurface 404, a lateral surface 416 a, and a standing feature 419 bondedto and extending from the PCD body 406 a to a height above the workingsurface 414 a. The standing feature 419 may be used to scoop, plow, cut,or combinations thereof into rock or earthen materials being cut by thePDC 400 a, or the standing feature 419 may stabilize the PDC 400 a whileit is traveling through rock or other earthen materials. The standingfeature 419 may extend to a non-zero height above the working surface414 a of about 100 μm or more, such as about 250 μm to about 10 mm,about 500 μm to about 8 mm, about 1 mm to about 5 mm, about 2 mm toabout 6 mm, about 2 mm, about 3 mm, or about 4 mm. As another example,the standing feature 419 may extend above the working surface 414 a ofthe PCD body 406 a to a height equal to about 1/20 the thickness of thePCD body 406 a or more, about 1/10 the thickness of the PCD body 406 ato about double the thickness of the PCD body 406 a, about ⅕ thethickness of the PCD body 406 a to about equal to the thickness of thePCD body 406 a, about ¼ the thickness of the PCD body 406 a to about ¾the thickness of the PCD body 406 a, about ⅓ the thickness of the PCDbody 406 a, about ½ the thickness of the PCD body 406 a, or about ⅔ thethickness of the PCD body 406 a. The standing feature 419 may exhibit athree-dimensional shape above the working surface 414 a of any shapedesired including, but not limited to, polygonal geometric shapes (e.g.,cubic, rectangular cuboid, trapezoidal pyramid, triangular prisms,square pyramids, triangular pyramids) cones, cylinders, amorphousshapes, rounded versions of the foregoing, shapes comprisingcombinations of the foregoing, and blended versions of combinations ofthe foregoing. The standing feature 419 may be located at or centeredabout any position on the working surface 414 a of the PCD body 406 a,such as but not limited to, a center of the working surface 414 a, aposition off of the center of the working surface 414 a, a position atthe outer periphery of the working surface 414 a (i.e., nearest thelateral surface 416 a), or combinations thereof.

The standing feature 419 may occupy a selected proportion of the workingsurface 414 a of the PCD body 406 a. For example, the standing feature419 may cover about 5 percent or more of the working surface 414 a ofthe PCD body 406 a, such as about 5 percent to about 95 percent, about10 percent to about 80 percent, about 20 percent to about 75 percent,about 30 percent to about 50 percent, about 20 percent, about 30percent, or about 40 percent of the working surface 414 a of the PCDbody 406 a.

As shown in the illustrated embodiment shown in FIG. 4A, the standingfeature 419 may exhibit a substantially rounded pyramid shape which mayhave a fin or scoop-like appearance. The standing feature 419 may extendabove the working surface 414 a to a height about equal to the thicknessof the PCD body 406 a and be positioned at a distance between a centerof the working surface of the PCD body 406 a and an outer periphery ofthe PCD body (i.e., near the lateral surface of the PCD body 406 a). Asexplained in more detail below, the PCD body 406 a having the standingfeature 419 thereon may be formed as a unitary piece (i.e., formed froma single diamond powder volume or formed using different layers orregions of diamond powders in the same HPHT process) using a mold.

Referring to FIG. 4B, a PDC 400 b may include a PCD body 406 bexhibiting a smaller lateral dimension than that of the substrate 402 itis bonded to. For example, the PCD body 406 b may include a workingsurface 414 b, a bonding surface 415 b, and a lateral surface 416 btherebetween. For example, the bonding surface 415 b may occupy lessthan 100 percent of an interfacial surface 403 of the substrate 402 towhich the PCD body 406 b is bonded, such as about 99 percent to about 10percent, about 90 percent to about 20 percent, about 80 percent to about30 percent, about 70 percent to about 40 percent, about 50 percent,about 60 percent, or about 75 percent. In the illustrated embodiment,the lateral surface 416 b has an angle of about 90 degrees with respectto the interfacial surface 403. The angle of the lateral surface 416 bmay be increased or decreased to control the area of the working surface414 b and/or the area of the bonding surface 415 b. For example, thelateral surface 416 b may form an angle relative to the interfacialsurface above about 30 degrees, such as about 45 degrees to about 135degrees, about 60 degrees to about 120 degrees, about 75 degrees toabout 105 degrees, about 45 degrees, about 60 degrees, about 75 degrees,about 95 degrees, or about 105 degrees.

Referring to FIGS. 4C and 4D, a PDC 400 c or 400 d may include a PCDbody 406 c or 406 d exhibiting a different lateral shape and/or sizethan that of the substrate 402 it is bonded to. The PCD body 406 c or406 d may include a working surface 414 c or 414 d, a bonding surface415 c or 415 d, and a lateral surface 416 c or 416 d therebetween. Inembodiments, the PCD body 406 c may exhibit a substantially annulargeometry including a cavity 420 (e.g., cut-out) therein. In such anembodiment, the PCD body 406 c may include an interior surface 418defining the cavity 420. In such embodiments, the substrate 402 c mayinclude a raised portion extending a height above the interfacialsurface 403 into the cavity 420; the raised portion may extend a heightsuch as to the working surface 414 c or less, such as about half way tothe working surface 414 c. In an embodiment (not depicted), thesubstrate 402 may include a through hole therein, with the through holesubstantially matching and aligned with the lateral dimensions of thecavity 420, or being otherwise within the lateral dimensions of thecavity 420 at the interfacial surface 403, to allow for coolant anddebris flow therethrough.

The lateral dimensions of the PCD body 406 c may be selected based onthe area of interfacial surface 403 c to bonding surface 415 c or areaof working surface substantially as described above. For example, theangle of the lateral surface 416 c and the interior surface 418 may beselected substantially as described above. The areas and angles may besubstantially similar to those described with respect to FIG. 4B.

In embodiments, the PCD body may have a different lateral shape comparedto the substrate and may be positioned anywhere on the interfacialsurface of the substrate. For example, the PCD body may only be locatedover only a portion of the substrate, such as substantially only overone half of the substrate, to thereby leave the portion of theinterfacial surface exposed. As shown in FIG. 4D, in an embodiment, aPDC 400 d including a PCD body 406 d may have a lateral shape differentthat the substrate 402 including, but not limited to, polygonal shapes(e.g., triangular, rectangular, etc.), oblong shapes, rounded shapes,semi-circular shapes, ovals, half circles, crescents, or combinations ofthe foregoing. For example, the PCD body 406 d having a crescent shapedisposed along at least a portion of the substrate interfacial surface403. The PCD body 406 d may have a working surface 414 d, a bondingsurface 415 d bonded to the substrate interfacial surface 403, and alateral surface 416 d extending therebetween.

Elements of any and all of the foregoing PDCs 400 a-400 d may becombined to form a PCD body either directly or indirectly bonded to asubstrate. For example, an annular- or crescent-shaped PCD body beingless than the full lateral dimension of an interfacial surface of asubstrate may include a standing feature extending from a workingsurface thereof, the PCD body being positioned off of the center of theinterfacial surface. In some embodiments, the PCD bodies shown in FIGS.4A-4D may extend laterally past the substrate to which it is bonded,such as a diameter or other lateral dimension of the PCD body may begreater than a diameter or other lateral dimension of the substrate.

Referring to FIGS. 5A-5D, a PDC may include, in addition to a PCD body,at least one additional PCD portion bonded to a substrate. Put anotherway, a plurality of PCD portions may be bonded to a substrate. Forexample, in embodiments, the additional PCD portions may be bonded to aninterfacial surface of the substrate, or to any surface of thesubstrate. Such additional PCD portions may be configured as fins, wearsurfaces, or rails, which may impart improved wear resistance, reduceheat checking, improve stability during cutting operations of the PDC,or combinations thereof. The PCD portions may extend away from thesubstrate to a selected distance about 100 μm or more, about 100 μm toabout 2 cm, about 500 μm to about 1 cm, about 1 mm to about 8 mm, about500 μm, about 2 mm, about 5 mm, or about 10 mm. The PCD portions mayextend away from the substrate in any number of orientations including,but not limited to, substantially parallel to a length of the substrate,substantially perpendicular to the length of the substrate, orcombinations of the forgoing. The shapes of the PCD portions describedabove may be similar to those described herein for any other PCDportion.

As shown in FIG. 5A, a PDC 500 a may include a PCD body 506 a having aworking surface 514 a, a bonding surface 515 a, and a lateral surface516 a therebetween. The PDC 500 a may further include a substrate 502having an interfacial surface 503 bonded to the bonding surface 515 a ofthe PCD body 506 a, and the substrate 502 may include one or more PCDportions 510 a thereon. The PCD portions 510 a may be bonded to thesubstrate 502 at the interfacial surface 503 thereof. The PCD portions510 a may be circumferentially spaced from each other on the interfacialsurface 503, which may include any type of spacing therebetween (e.g.,equidistant spacing, clustered, or random). The PCD portions 510 a maybe distributed about only a portion (e.g., one side) of the interfacialsurface 503 of the substrate 502 or may be concentrated more in oneregion of the substrate 502. The PCD portions 510 a may prevent or limitwear of the interfacial surface 503 of the substrate 502 during use. ThePCD portions 510 a bonded to the interfacial surface 503 may have anyorientation including direction and spatial orientations. For example,the PCD portions 510 a may be separate from or touch the PCD body 506 a.The PCD portions 510 a may extend from an interior location to thesurface 504 of the substrate 502 or remain inside the boundary of theinterfacial surface 503 only.

As shown in FIG. 5B, a PCD 500 b may include a PCD body 506 b bonded toan interfacial surface 503 of the substrate 502, and a PCD portion 510 bbonded to the substrate 502 at a surface 504 thereof. The PCD portion510 b may be positioned at any point on the surface 504 of the substrate502. For example, the PCD portion 510 b may abut the PCD body 506 b nearthe interfacial surface 503 of the substrate 502, or the PCD portion 510b may be spaced from the PCD body 506 b. The PCD portion 510 b may runlongitudinally substantially parallel to a length the substrate 502,such as depicted, or may extend in any other direction such aslongitudinally substantially perpendicular to a length of the substrate502. The PCD portion 510 b is depicted as a semi-circular rail or finextending away from the surface 504 of the substrate 502. However, theshape of the PCD portion 510 b may be any shape disclosed herein for PCDportions, such as substantially flat (e.g., a three dimensionalpolygonal). The PCD portion 510 b may run any length, portion, ordistance along the substrate 502 such as by way of non-limiting example,a portion of or the entire longitudinal dimension of the surface 504 ofsubstrate 502, a portion or the entire circumferential dimension of thesurface 504 of the substrate 502, or a discrete point or region on thesurface 504 of the substrate 502.

In some embodiments, a plurality of PCD portions may be bonded to asubstrate. For example, as shown in FIG. 5C, a plurality of PCD portions510 c may be bonded to the surface 504 of the substrate 502. The PCDportions 510 c may be circumferentially spaced from each other on thesurface 504 of the substrate 502, or may be distributed in any othermanner on the surface 504 of the substrate 502 (e.g., randomly,longitudinally, laterally, or combinations of the foregoing). As shown,the PCD portions 510 c may be oriented to run in a longitudinallysubstantially parallel manner to a length of the substrate 502, or maybe oriented to run in substantially perpendicular to the length of thesubstrate 502. The PCD portions 510 c may be spaced from each other onthe surface 504 in any manner, such as equidistant from one another,randomly, concentrated in one region of a surface more than others, onlyon a particular region of the substrate, or combinations of theforegoing. For example in FIGS. 5C and 5D, the PCD portions 510 c areonly located on one half of the side surface 504 of the substrate 502 tofacilitate positioning of the PDC 500 c into a bit body 561 of a rotarydrill bit 560. The PCD portions 510 c may provide wear resistancefeatures that protect and/or reduce heat checking of the substrate 502and/or provide stability through a rock or earthen material duringcutting operations.

The PCD bodies, substrates and PCD portions extending from a surfacethereon disclosed herein may be made using molds and molding techniquesas described below. Referring to FIGS. 6A-6E, an endmill may be madeusing a mold 632 having a mold cavity 634 including at least one fluterecess 636 therein. The mold 632 may include an outer surface 633 and anupper surface 635. The mold cavity 634 may be an elongated generallycylindrical cut out, a wide generally cylindrical cut out, or any othershape suitable to insert a substrate (e.g., shaft or shank) therein. Theflute recesses 636 may be disposed in the mold cavity 634 in any mannersuch as, but not limited to, generally helically extending about aninner periphery of the mold cavity 634, longitudinally substantiallyparallel to a length of the mold cavity, substantially perpendicular toa length of the mold cavity 634, or combinations of the foregoing. Themold cavity 634 may exhibit a diameter Ds or other lateral dimensionselected to allow the substrate having a diameter Ds to be inserted intothe mold cavity 634 such that the substrate surface is in contact withthe mold cavity inner surface when positioned therein. The fluterecesses 636 may exhibit a negative geometry sufficient to produce atool having a width W substantially similar to any width W describedabove, and a standoff distance S substantially similar to any describedabove. The mold cavity diameter Ds and the sum of the standoff distancesS may equal the total diameter Dt, such as any of those described above,results in a cutting tool formed therein exhibiting the substantiallythe same dimensions. The mold cavity lengths, as used in any embodimentherein, may be about 2 cm to about 50 cm, such as about 3 cm to about 40cm, about 4 cm to about 30 cm, about 2 cm to about 20 cm, about 3 cm toabout 15 cm, about 4 cm to about 12 cm, about 6 cm, or about 7 cm.Molds, as used in any embodiment herein, may be correspondingly widerand longer than the mold cavities including flute recesses disclosedsuch as, for example, wider and/or longer than the mold cavities andrecesses by about 5% or more, such as about 10% to about 30%, about 15%,or by about 2 mm or more, such as about 2 mm to about 3 cm, about 5 mmto about 20 cm, or about 1 cm larger than the maximum extent of any moldcavity including any flute recess therein.

As shown in FIG. 6B-6D, a substrate 602 may be inserted into the moldcavity 634 such that surface of the substrate 602 is in contact with theinner surface of the mold cavity 634, while the flute recesses 636 maybe substantially empty or may be filled with a material (e.g., diamondpowder). The substrate 602 may include any composition or configurationdescribed herein for a substrate. Diamond material 608 may fill theflute recesses 636. By way of non-limiting example, diamond materials608 may include loose or free diamond particles or powder,shear-compacted tape having diamond particles therein, diamond powderheld by a binder (e.g., by a wax or polymer), agglomerates of diamondparticles or powder, any other suitable diamond material, orcombinations of one or more of any of the foregoing. Suitable diamondmaterials include any of those described in U.S. Pat. Nos. 7,806,206 and8,316,969, each of which is incorporated herein, in its entirety, bythis reference. Suitable diamond powders may include any of thosedisclosed herein, including but not limited to, average diamond particlesize, number of modes, catalyst content and amount, or combinations ofthe foregoing. The diamond material 608 may be positioned in the fluterecess 636 by pouring the diamond material 608 into each individualflute recess 636 once the substrate 602 has been positioned within themold cavity 634. To ensure that the diamond material 608 occupies eachflute recess 636 substantially completely (e.g., the entire volume ofthe flute recesses 636 are filled with the diamond material 608), thediamond material 608 in the mold assembly 630 (i.e., mold, substratetherein, and diamond powder positioned in the flute recesses) may becompacted. In order to compact or otherwise consolidate the diamondmaterial 608 in the mold 632, the mold 632 may be subjected to agitationincluding but not limited to, tumbling, a shaker table, ultrasonicagitation, or combinations thereof.

Referring to FIG. 6D, after forming the mold assembly 630, the moldassembly 630 may be placed into a refractory metal container (e.g., can)which is then loaded into a suitable pressure transmitting medium suchas, by way of non-limiting example, pyrophyllite. The pressuretransmitting medium containing the mold assembly 630 may then besubjected to an HPHT process, including HPHT conditions substantiallysimilar to any described herein, effective to sinter the diamondparticles in the diamond material 608 and bond the resulting PCDportions to a surface of the substrate 602. During the HPHT process, acatalyst material (e.g., cobalt), mixed with the diamond material (e.g.,diamond powder) and/or present in the substrate 602 may melt and sweepinto the interstitial spaces between diamond particles and, uponcooling; the catalyst material may form a mechanical and/or chemicalbond between the PCD portion and the substrate 602.

As shown in FIG. 6E, a cutting tool 600 e may be removed from the mold632 after HPHT processing. The cutting tool 600 e may be removed fromthe mold 632 by any technique sufficient to remove mold material from apart or vice versa, such as, pressure/media blasting, dissolution,breaking away pieces of the mold, uncoupling the mold, or combinationsof the foregoing. The resulting cutting tool 600 e may be configured asan endmill having the substrate 602 including the surface 604 having thePCD portions 610 bonded thereto an imperforate portion of the surface604. That is, the PCD portions 610 are bonded to a portion the surface604 that does not include recesses formed therein. Optionally, a facecutting endmill (not depicted) may be formed by including PCD portionson an end surface 604 e (e.g., facial surface) of the substrate 602.

Suitable molds for any of the embodiments herein may be formed using anumber of techniques including, but not limited to, obtaining orcreating a part having positive dimensions (such as by wax printing orrapid prototyping machines), investment casting or pressing (e.g.,isostatically pressing or molding) a mold of the part, removing the partfrom the mold (e.g., by twisting the part out, or by cutting the moldinto recombinable portions), and saving the mold having a negativeimpression of the part therein to be used in the processes describedherein. Such molds may include casting a rubber mold or multi-piecemold. In some embodiments, a mold may be made by casting a solid moldblank using a machinable and/or pressable medium such as, but notlimited to, hexagonal boron nitride (“HBN”), alumina, Talc, graphite,salt, a ceramic material, other powders amenable to being pressed, orcombinations of the foregoing; and/or cutting/machining a mold cavity(e.g., hole) therethrough to accommodate a substrate, and then cuttingflute recesses into the mold cavity in any desired configuration. Themachining may be performed using milling techniques (e.g., conventionalmilling (e.g., vertical or horizontal milling), thread cutting,extrusion, etc.), lasing, electro-discharge machining (“EDM”), orcombinations of the foregoing. In some embodiments, as described in moredetail below, a mold may be formed by directly three-dimensional (“3-D”)printing a refractory metal can in the shape of a mold defining a moldcavity including flute recesses therein. In an embodiment, the interiorsurface of the mold cavity may be coated with a material that will notfowl or contaminate formation of the PCD and/or PCD to substrate bondingprocess. Suitable coatings may include HBN or a refractory metal, andmay be in the form of a film, paint, foil, powder, or combinations ofthe foregoing. Suitable materials for molds being cast or machinedinclude any of those materials stated above.

In some embodiments, such as that shown in FIGS. 6F-6G, a mold 632 f mayinclude one or more alignment recesses 638 f formed therein. Thealignment recesses 638 f may be positioned on the interior surface of amold cavity 634 f and extend inwardly from the upper mold surface 635 fa distance therein. The alignment recess 638 f may be positioned suchthat debris slots 605 f formed in a corresponding substrate 602 finserted into the mold cavity 634 f may substantially align with (e.g.,extend substantially congruent with) the at least one flute recess 636 fformed in the mold cavity 634 f. Such a configuration may facilitatethat a resulting PCD portion formed therein may push cut debris throughthe debris slot 605 f aligned therewith (e.g., in front of a cuttingface formed from the PCD portion), and/or may facilitate that, duringformation of the cutting tool, substantially no diamond powder poured orpositioned in the at least one flute recess 636 f falls into the debrisslots 605 f on the substrate 602 f.

As shown in FIG. 6G, when the alignment protrusions 645 f of thesubstrate 602 f are inserted or otherwise aligned with the alignmentrecesses 638 f in the mold 632 f, the flute recesses 636 f are adjacentto, without overlapping, the debris slots 605 f defined by the substrate602 f. The act of assembling a mold assembly may include aligning anyalignment recesses and protrusions therein. After aligning the substrate602 f with the mold 632 f using the alignment protrusions 645 f andalignment recesses 638 f, diamond material such as any described hereinmay be poured or otherwise inserted into the flute recesses 636 ftherein to form the mold assembly 630 f. In another embodiment, thediamond material may be positioned within flute recesses 636 f and thenthe substrate 602 f may be positioned within the mold 632 f.

The mold assembly 630 f may be loaded into a refractory metal container,which may be further loaded into a pressure transmitting medium. Thepressure transmitting medium including all of the above contents may beloaded into an HPHT press in which the pressure transmitting medium andthe contents thereof are subjected to HPHT conditions substantialsimilar to any described herein. After cooling, the mold 632 may beremoved, leaving only the cutting tool 600 f including the substrate 602f having the debris slots 605 f therein, the PCD portions 610 f adjacentto the debris slots 605 f bonded to the surface of the substrate 602 f,and the alignment protrusions 645 f extending laterally from the endsurface of the substrate 602 f.

The cutting tool 600 f may be further finished after removal from themold such as, by way of non-limiting example, removing the alignmentprotrusions 645 f using machining (e.g., EDM), lasing, grinding, orbreaking; or lapping the end surface of the substrate 602 f or the PCDportions 610 f bonded to the surface of the substrate 602 f. Inembodiments, finishing may include final adjustments to the surfacefinish of a portion of the cutting tool 600 f, removing some PCDmaterial to smooth a rough surface or provide a desired dimension,removing some PCD material to form thread cutting bodies, removingportions of the substrate to form debris slots, or combinations of theforegoing.

In some embodiments, more generally, debris slots in the substrate mayhave many configurations. For example, debris slots may extendsubstantially congruent to the PCD portions on the substrate, or mayextend non-parallel thereto. The debris slots may exhibit across-sectional geometry such as, but not limited to, generallyrectangular, rounded (e.g., semi-circular as shown in FIG. 6H), ortriangular. The debris slots may extend a depth into the substrate fromthe surface thereof such as, by way of non-limiting example, about 100μm or more, about 500 μm to about 2 cm, about 1 mm to about 1 cm, about2 mm to about 8 mm, about 1 mm, or about 2 mm. Debris slot may extend awidth, around a circumference of the substrate, of about 100 μm or more,about 500 μm to about 3 cm, 1 μm to about 2 cm, about 1 mm to about 1cm, about 2 mm to about 8 mm, about 2 mm, or about 4 mm. Debris slotsmay be adjacent (e.g., extend substantially congruent with) to PCDportions with or without overlapping, or may be spaced a distancetherefrom. Any number of debris slots may be used on a cutting tool. Thenumber of debris slots and PCD portions may be the same as or may bedifferent from each other. For example, by way of non-limiting example,cutting tools may have one or more PCD portion (e.g., two or three)thereon and one or more debris slots (e.g., two or three) therein (suchas depicted in FIG. 6H). In an embodiment, a cutting tool may have fourPCD portions thereon and two debris slots therein. Molds may becorrespondingly manufactured to produce any of the cutting toolsdescribed herein, or individual features described therewith.

In some embodiments, one or more alignment protrusions and recesses maybe used such as one, two (as shown in FIGS. 6F-6H), three, or four ormore. The alignment protrusions and corresponding alignment recesses mayhave many different sizes and configurations. For example, the alignmentprotrusions and recesses may be configured as polygonal, rounded, orother suitable shapes extending into the interior surface of a moldcavity. The alignment protrusions and recesses may extend a distanceinto the interior surface of about 500 μm or more, such as about 500 μmto about 2 cm, about 1 mm to about 1 cm, about 2 mm to about 8 mm, about3 mm, about 5 mm, or about 6 mm. In some embodiments, the alignmentprotrusions and alignment slots may exhibit a width from one side toanother of about 500 μm or more, such as about 500 μm to about 2 cm,about 1 mm to about 1 cm, about 2 mm to about 8 mm, about 3 mm, about 5mm, or about 6 mm. Additionally, standoff distances S, number of PCDportions, number of debris slots, width of PCD portions, number and/orconfiguration of alignment protrusions and recesses, combinationsthereof or any other characteristic of a cutting tool or mold formmaking same may be adjusted based on the desired size of the substrateand/or finished tool. By way of non-limiting example, a cutting toolhaving a comparatively larger diameter substrate may use larger PCDportions including a larger standoff distance S and/or larger width W,more PCD portions, or more debris slots therein.

Referring to FIGS. 7A-7D, a cutting tool 700 (as shown in FIG. 7D)configured as a drill may be made using a mold 732. The mold 732 mayinclude an outer surface 733, a base surface 737, and an upper moldsurface 735. The mold 732 may have a mold cavity 734 (e.g., molded ormachined) therein. The mold cavity 734 may include an end-region recess739 at a distal end (e.g. deepest extent) of the mold cavity, and one ormore flute recesses 736 extending from the end-region recess 739 andoptionally, on any other portion of the mold cavity 734 (e.g., interiorsurface). The end-region recess 739 may exhibit any geometricconfiguration such as, but not limited to, conical, domed, pyramidal,stepped, or combinations thereof. The one or more flute recesses 736 mayextend from a center point of the end-region recess 739 to an outerlateral portion of the end-region recess 739, or may extend from a pointat least intermediate to the center of the end-region recess 739 and anouter lateral portion of the end-region recess 739 to the outer lateralportion of the end-region recess 739. The one or more flute recesses mayextend longitudinally away from the end-region recess by a standoffdistance S, such as any of the distances S described herein.

In some embodiments, such as shown in FIG. 7B, the flute recesses 736may align with each other along a center line C (e.g., bisecting theinterfacial surface into equal halves) of the end-region recess 739 toextend co-linearly across the end-region recess 739. The flute recesses736 may be positioned off of the center line C in the end-region recess739, such as in a staggered configuration in which each PCD portionabuts the center line C. In embodiments having more than two fluterecesses, the flute recesses 736 may be positioned radially around theend-region recess 739 in an equidistant manner, and may be centered onone of a plurality of center lines C radially corresponding to the fluterecess 736, spaced off of the center line C radially corresponding tothe flute recess 736 a distance, or abut the center line C radiallycorresponding to the flute recess 736. The flute recesses 736 may bepositioned on the end-region recess 739 to create a PCD portion 710defining a cutting edge positioned to correspond to the leading side ofrotation of a cutting tool.

Optionally, at least one sprue hole 740 may be formed in a surface ofthe mold 732, the sprue hole extending to at least one of the at leastone flute recesses 736. The sprue hole 740 may extend through the basesurface 737, the upper mold surface 735, or the outer surface 733. Thesprue hole 740 may be used to pour or otherwise position diamondmaterial (e.g., diamond powder) in the flute recesses 736 once thesubstrate 702 is positioned in the mold cavity 734. As shown in FIG. 7C,the sprue hole 740 may be used to position diamond material in an angledcavity when the substrate is positioned therein in order to allow thediamond material to remain in the flute recess 736 alone. For example,if the diamond material is poured into the flute recesses 736 in theend-region recess 739 being configured at an angle, the diamond materialmay flow to the bottom of the end-region recess 739 rather than remainin the flute recesses 736. In order to overcome this problem, the entiremold may be oriented (e.g., tipped upside down) such that diamondmaterial (e.g., diamond powder) may be poured into the sprue hole 740 sothat the diamond material may fill the flute recesses 736 therein. Thediamond material may be compacted or otherwise agitated as describedherein to ensure substantially complete occupation of the fluterecesses. In another embodiment, shear-compacted diamond material ordiamond material with a binder may be positioned in flute recesses 736and then substrate 702 may be positioned in the mold.

As described in more detail below, the diamond material may be insertedinto the flute recesses 736 prior to inserting the substrate 702 intothe mold cavity 734. Such diamond material may be pre-compacted into theflute recesses 736 (e.g., cold pressed). In some embodiments, thediamond material such as a diamond powder may have a binder materialtherein, such as a material to make the diamond powder malleable whilethe binder is wet and at least temporarily bond to itself and a surfaceupon curing. The diamond material may be encapsulated by or in anothermaterial at the flute recesses 736 (e.g., a layer of material holdingthe diamond material in the flute recess, or a tube filled with diamondmaterial such as diamond powder inserted (e.g., compressed, tension fit,or compacted) into the flute recess 736). In an embodiment, aftertemporarily bonding the diamond material to the substrate, the mold maybe removed to expose the substrate having diamond material thereon, thesubstrate and diamond material may then be wrapped with in a metal foiland salt for pre-compaction. The resulting assembly may then besubjected to HPHT conditions such as any described herein.

In an embodiment, a method of forming a cutting tool using the moldassembly 730. The mold assembly 730 may include the mold 732 having themold cavity 734, wherein the mold cavity 734 may include the end-regionrecess 739 at a distal extent of the cavity 734. The mold 732 mayfurther include at least one flute recess 736 therein. The mold assembly730 may include the substrate 702 positioned within the mold cavity 734,effective to contact the inner surface of the mold 732 substantiallycontinuously throughout, except for the flute recesses therein. Diamondmaterial such as diamond powder may be positioned within the fluterecesses 736 by pouring the diamond powder into the flute recesses 736directly or through a sprue hole, pre-compacting the diamond materialinto the mold recesses prior to insertion of the substrate, or using amaterial to hold the diamond material in the flute recesses 736. Themold 732 may be formed using any of the materials and/or techniques forforming a mold disclosed herein. The mold assembly 730 may be placed ina refractory metal container which may be placed in a pressuretransmitting medium, which is loaded into a press, wherein the assemblyis subjected to HPHT conditions sufficient to sinter the diamondmaterial to the surface of the substrate. The refractory metal can,pressure transmitting medium, and HPHT process may be substantiallysimilar to any described herein.

After HPHT processing, the mold material may be removed from thesubstrate, by any of the removal techniques described herein, therebyexposing the cutting tool 700. The cutting tool 700 may include thesubstrate 702 body having a surface 704, an end surface 703 and at leastone PCD portion 710 thereon. The geometry of the end surface 703 mayresemble any of the geometries described herein for the end-regionrecess 739. The geometry of the substrate (size) may substantiallycorrespond to the geometry of any substrate described herein. Thestandoff distance may be any standoff distance recited herein. Thenumber and position of PCD portions 710 may correspond to any positionand/or number of flute recesses recited herein.

In an embodiment (not shown), a mold and corresponding substrate mayhave alignment protrusions and recesses substantially similar to thosedescribed above. The alignment recesses and protrusions may be used toalign debris slots in the substrate with the flute recesses of the mold.For example, a cutting tool may include a substrate having at least onedebris slot therein extending (e.g., helically or linearly) along asurface thereof to an apex (e.g., center) of an end surface of thesubstrate, at least one alignment protrusion extending from the surfaceof the substrate (e.g., laterally extending), and at least one PCDportion adjacent to the debris slots. The corresponding mold, from whichthe cutting tool may be formed, may include a mold cavity including anend-region recess having flute recesses extending therefrom, analignment recess corresponding to the alignment protrusion on thesubstrate, and optionally a sprue hole. The debris slots, alignmentrecesses and protrusions, and remaining portions of the molds orsubstrates may be substantially similar to any described herein.

Referring to FIGS. 8A-8C, a cutting tool may be formed by positioning atleast one diamond material tube 870 (or other diamond material flutevolume) having at least one wall 872 at least partially enclosingdiamond material (e.g., diamond particles or powder) therein around asubstrate 802, which may be placed in a mold 832 to form a mold assembly830. The mold assembly 830 may be subjected to HPHT conditions effectiveto melt a catalyst material forming the at least one wall 872 of thediamond material tube 870, bond the diamond particles in the diamondmaterial 808 together, and bond the resulting PCD portion 810 to thesubstrate 802.

The material used to form the at least one wall 872 of the diamondmaterial tube 870 should be malleable enough to extend or otherwise wraparound substrates having a small diameter (e.g., about 1 mm) withoutbreaking or tearing. Suitable materials may include iron, cobalt,nickel, tungsten carbide embedded in cobalt, alloys or mixtures of theforegoing, or any other material that may catalyze diamond-to-diamondbonding while remaining compliant enough to wrap around a small diameterwithout breaking or tearing. In embodiments, the at least one wall 872material may be substantially free of any plastics, polymer, or wax, oruse very little plastic, polymer, or wax therein in order to eliminateor reduce contamination or fowling of the PCD body to be formed due toinfiltration of plastic material. For example, the diamond material tube870 (e.g., flute tube) may be provided or formed without any plastic,polymer, or wax therein.

As shown in FIGS. 8B and 8C, the diamond material tube 870 may have anoutside diameter (“OD”) and an inside diameter (“ID”); the difference ofwhich is the wall thickness. The diamond material tube 870 may have anOD substantially equal to or slightly larger (e.g., 10 percent larger)than any of the standoff distances S recited herein. In an embodiment,the ID of the diamond material tube 870 may be about any size ofstandoff distance S recited herein less two times any wall thicknessrecited herein. The inside diameter of the tube may filled with anydiamond material, such as diamond powder, as described herein.

In some embodiments, the at least wall 872 of the diamond material tube870 may be as thin as possible without causing breaking or tearing inthe resulting diamond material tube 870, such as about 50 μm thick ormore, about 150 μm to about 1 mm, about 250 μm to about 800 μm, about250 μm to about 600 μm, about 150 μm to about 500 μm, about 250 μm, orabout 500 μm.

While shown as substantially cylindrical, the cross sectional shape ofthe diamond material tube 870 may have a generally polygonal crosssectional shape, generally elliptical cross-sectional shape, oblongcross sectional shape, a substantially flattened cross sectional shape,or combinations of the foregoing. The diamond material tube 870 mayexhibit more than one cross-sectional shape along the length thereof.For example, one end of the diamond material tube 870 may exhibit asubstantially rectangular cross-sectional shape, wherein another end ofthe diamond material tube 870 may exhibit a substantially roundcross-sectional shape. It is understood that the process of wrapping andor attaching a diamond material tube to a substrate or mold may deformthe shape and/or diameter of the diamond material tube to some extent.

The diamond material tube 870 may be provided or may be formed using atube having a desired cross-sectional size. For example, the diamondmaterial tube 870 may be made using tape, a strip, a foil, or a sheetcomprised of the materials stated above useful for forming one or morewalls 872. The tape, strip, foil, or sheet width may be equal to orgreater than the circumference of any diamond material tube 870 sizerecited herein (as determined by the outside diameter measurementsrecited herein). The thickness of the tape, strip, foil, or sheet may beequal to any of the wall thicknesses recited above. In an embodiment,tape, strip, foil, or a sheet (e.g., such as comprising cobalt), mayexhibit a thickness of about 250 μm and width of about 2 mm or more.Diamond material 808 (e.g., diamond powder) may be poured or otherwisepositioned centrally relative to the width of the tape, strip, foil, orsheet. The sides of the tape, strip, foil, or sheet may then be folded,positioned, or wrapped around the diamond material 808 to form thediamond material tube 870 having diamond material 808 therein. The sidesof the tape, strip, foil, or sheet may overlap each other to ensure thediamond material 808 does not fall out of the diamond material tube 870during use. The width of the tape, strip, foil, or sheet may be selectedto overlap (e.g., wrap around or surround) the diamond material 808 morethan one time. In an embodiment, a portion (e.g., length) of tape,strip, foil, or sheet may have diamond material disposed along a portionintermediate to the sides and/or ends thereof. Another portion of tape,strip, foil, or sheet may be placed over top of the diamond material andfirst portion of tape, strip, foil, or sheet sufficient to cover thediamond material and at least partially overlap the first portion oftape, strip, foil, or sheet. The two portions of tape, strip, foil, orsheet may be twisted, folded, swaged, deformed, or wrapped around eachother to seal the diamond material inside. Other types of diamondmaterial flute volumes may be employed besides the illustrated diamondmaterial tube 870. In some embodiments, the at least one diamondmaterial tube 870 may be replaced by at least one preformed diamondflute volume including diamond powder that has been shear compacted witha suitable polymeric binder. In such an embodiment, the at least onepreformed diamond flute volume may be a substantially uniform body thatmay be bent like a tube. Suitable green tapes and other diamond productsare commercially available from Ragan Technologies Inc. of Winchendon,Mass. using High Shear Compaction (HSC™) process(es).

As shown in FIGS. 8A and 8D, the at least one diamond material tube 870may be positioned around or adjacent to the substrate 802 (e.g.,helically, or longitudinally). The diamond material tube 870 may betemporarily attached to the surface 804 of the substrate 802 by at leastattaching discrete (e.g., small) portions of the diamond material tube870 to the substrate 802 by tack welding, adhesive bonding, inductiveheating, laser tacking, or other suitable methods. Once the at least onediamond material tube 870 is positioned on the substrate 802, the atleast one diamond material tube 870 and substrate 802 may be coated witha refractory metal foil or refractory paint or paste capable ofwithstanding sintering pressures and temperatures, such as by way ofnon-limiting example, Pyro-Paint™ produced by Aremco Products Inc., ofNew York or one of the aerosol refractory paints (e.g., Z aerosol)produced by ZYP Coatings, Inc., of Tennessee. The at least one diamondmaterial tube 870 and substrate 802 may then be pre-compacted in a moldmaterial, such as any described herein to form the mold assembly 830.The mold assembly 830 may be loaded into a refractory metal can, or maybe loaded directly into a pressure transmitting medium, all of which maybe subjected to HPHT conditions sufficient to sinter diamonds particles,whereby the at least one wall 872 may at least partially melt and thecatalyst material therein may catalyze diamond-to-diamond bonding, andthe resulting PCD portions may bond to the surface 804 of the substrate802 upon cooling.

As shown in FIG. 8E, a cutting tool 800 formed according to theforegoing may include PCD portions 810 resembling flutes extendingaround and bonded to the surface 804 of the substrate 802. The surface804, as shown, may be substantially cylindrical and PCD portions 810 maybe bonded thereto. Optionally, the PCD portions 810 may be positioned onthe end surface 803 of the substrate 802, in addition to oralternatively to being positioned on the surface 804 (e.g., lateral orside surface) of the substrate 802. The PCD portions 810 formed from thediamond material tube 870 may require surface finishing to form a finalshape, diameter, or cutting edge. For example, a substantially rounddiamond material tube 870 may form a substantially rounded PCD portion810, which may require further processing to form a sharp cutting edgethereon, or square up the PCD portions 810. Surface finishing may beaccomplished using milling techniques, EDM, lasing, grinding, lapping,or combinations of the foregoing.

In an embodiment, such as shown in FIG. 8F, the mold 832 may have fluterecesses 836 formed in a mold cavity 834. The mold cavity 834 and fluterecesses 836 may be substantially similar to and may be made insubstantially the same manner as any described herein. Diamond materialtube(s) 870 may be positioned within the flute recesses 836 prior toinsertion of a substrate 802 into the mold cavity 834. After insertionof the substrate 802 into the mold cavity 834, the assembly may be HPHTprocessed as previously described.

In an embodiment, the diamond material tubes 870 may be placed in theflute recesses 836 with a binder material on and/or in one or both ofthe diamond material tubes 870 and flute recesses 836. As shown in FIG.8G, the substrate 802 may be positioned in the mold 832 having diamondmaterial tubes 870 in the flute recesses 836 therein prior to curing toform the mold assembly 830. After curing, the binder material maytemporarily or weakly attach the diamond material tube 870 to thesurface 804 of the substrate 802. The mold material may be removed(e.g., stripped away), after which the substrate 802 including thediamond material tubes 870 thereon may be encased or coated in arefractory metal (e.g., a foil). Then, an additional pressuretransmitting material 880 (e.g. pyrophyllite, or salt) may be positionedabout the assembly, after which the assembly may be subjected to HPHTconditions effective to sinter the diamond particles in the diamondmaterial and bond the resulting PCD portion to the substrate 802. In anembodiment, the mold material may be rubber, latex, or mixturescomprising the same (e.g., rubber mold), wherein after curing thediamond material tubes 870, the rubber mold may be removed from (e.g.,stretched or deformed off) the substrate and diamond material tubes forreuse. Rubber molds may be used in any process described herein wherethe mold material is removed from the substrate prior to sintering.

A cutting tool substantially similar to that depicted in FIG. 3 may bemolded or otherwise manufactured using any of the processes describedherein, including forming recesses for thread cutting bodies and/orfinishing PCD portions to form thread cutting bodies therein.

Referring to FIG. 9, in an embodiment, a mold 930 may include or may beformed from a metallic can defining a mold cavity 934 having at leastone flute recess 936 therein. The metallic can may comprise anyrefractory metal, non-refractory metal, or alloys of any of theforegoing. In an embodiment, the metal can may be formed with arelatively thin wall thickness of metallic material such that the moldcavity 934 may substantially define the geometry of a sintered cuttingtool. In an embodiment, the metal can may include tungsten, cobalt,titanium, steel, nickel, or combinations of the foregoing. In anembodiment as shown in FIG. 9, the surface 933 (e.g., outer surface) ofthe mold 930 may be substantially congruent with the mold cavity. In anembodiment (not shown), the surface 933 may be incongruent with the moldcavity, such as a mold 930 having a generally cylindrical mold cavity934 and a generally cuboid surface 933. In some embodiments, the mold930 comprising the metallic material may be formed by isostaticpressing, molding, or 3-D printing a metal can in the shape of apositive form of a substrate having PCD portions thereon. 3-D printing(e.g., laser sintering, metal sintering) of metals and refractory metalsmay be achieved by using a suitable 3-D metal printer, such as, but notlimited to those available from 3D Systems Corp. of U.S.A, EOS GmbH ofGermany, Arcam AB of Sweden, or ExOne Co. of the U.S.A. and Japan. Theaverage wall thickness of the 3-D printed metal can may be about 0.003inches or more, such as about 0.003 inches to about 0.02 inches, about0.005 inches to about 0.05 inches, about 0.005 inches to about 0.01inches, about 0.011 inches to about 0.015 inches, about 0.005 inches,about 0.011 inches, about 0.012 inches, about 0.014 inches, about 0.015inches, or less than about 0.015 inches. For example, a Ti-6Al-4V alloy(e.g., Grade 5) or other titanium alloy may be printed in a metal canshape substantially as shown in FIG. 9 or any other suitable shape. TheTi-6Al-4V alloy can may exhibit an average wall thickness of about 0.011inches to about 0.015 inches (e.g., about 0.014 inches). Other metals(e.g., refractory metals, or refractory metal containing alloys) may beused to 3-D print a metal can as described herein.

In an embodiment, a mold 930 may be produced by 3-D printing, and thenthe surface (e.g., inner surface and/or outer surface) of the mold 930may be coated with a refractory metal. Refractory metal coatingtechniques may include chemical vapor deposition (“CVD”), physical vapordeposition (“PVD”), electroplating, or other suitable technique fordepositing a refractory metal on a surface. Optionally, the originalmold material may be removed leaving the refractory metal in place.

In an embodiment of a method of making a cutting tool, a mold in theform of a metal container (e.g., refractory metal can) may be formed bycreating a positive form of a cutting tool. The metal container may beformed by placing a finished cutting tool inside of the metal containersomewhat larger than the cutting tool. Optionally, the metal containermay be placed in a pressure transmitting medium. The mold may be made bycompressing the metal container around the cutting tool until the metalcontainer takes the shape of the outer surface of the cutting tool. Thecutting tool may be removed from the compressed metal container (i.e.,mold. The cutting tool may be removed by withdrawing the cutting toolout through the compressed metal container (such withdrawal may requiretwisting if cutting tool includes helical flutes). Removal may includeleaching the cutting tool out of the mold, shot blasting the cuttingtool out, stretching the mold, or cutting the mold into a multiplicityof pieces sufficient to be reused as the mold once combined again (e.g.,cut in half longitudinally).

The mold 930 may have a wall thickness sufficient to allow HPHTconditions to apply pressure to the contents thereof while beingresilient enough to stand on its own. The wall thickness may becomparable to or thicker than wall thickness of the diamond tube wallsdescribed herein.

In an embodiment, a mold, such as any described herein, may be include aceramic material (e.g., HBN containing ceramic or alumina). For example,the ceramic material may be 3-D printed in the shape of any molddescribed herein.

Molds and methods of making and using the molds, substantially similarto any described herein, may be used to form PDCs having featuresstanding off of the PCD body or substrate therein, such as for example,those depicted in FIGS. 4A-4D and 10B. In an embodiment, such as shownin FIG. 10A, a mold 1032 a may have a mold cavity 1034 a thereinincluding a PCD body cavity or recess 1058 a and at least one standingfeature recess 1059 a extending from the PCD body cavity or recess 1058a. The PCD body cavity or recess 1058 a may exhibit a geometryconfigured to produce any of the PCD bodies 406 a-506 c or any of thevariants described in relation thereto, including but not limited to,PCD body size, shape, standing features, orientation on the substrate,and combinations thereof. The standing feature recess 1059 a may beconfigured to produce any of the standing features 419 or variationsthereof, including but not limited to, shape, size, orientation,position in relation to PCD body, number, or combinations of theforgoing. The mold 1032 a may be formed using any of the techniques andmaterials described herein without limitation. An assembly for forming aPCD according to FIGS. 4A-4D may be made using any substrate asdescribed herein including materials, sizes, shapes, and combinationsthereof. The assembly may be placed in a refractory metal containerand/or in a pressure transmitting medium substantially similar to anydescribed herein. The assembly may be subjected to HPHT conditionssubstantially similar to any of those described herein. After the HPHTprocessing, the mold material may be removed to reveal the PDC.

A cutting tool formed according to the preceding process and using themold depicted in FIG. 10A may resemble the cutting tool 1000 depicted inFIG. 10B. The cutting tool 1000 may be configured as a PDC including aPCD body 1006 a having a standing feature 1019 a extending therefrom.The cutting tool 1000 may further include a substrate 1002 having asurface 1004 (e.g., outer or lateral surface) and an interfacial surface1003 bonded to the PCD body 1006 a. In some embodiments, PDCs and PCDbodies formed using molds and molding techniques described herein mayresemble any of those described herein, including variations thereof.

In an embodiment, such as that shown in FIG. 10C, a mold 1032 c mayinclude an outer surface 1033 c, an upper mold surface 1035 b, a moldcavity 1034 c, and optionally, at least one sprue hole (not depicted).The mold cavity 1034 c may include a PCD body cavity 1058 c and at leastone standing feature recess 1059 c therein. The standing feature recessmay extend from the PCD body cavity 1058 c as shown in FIG. 10A or mayextend from the inner surface of the mold cavity 1034 c adjacent towhere the substrate may be positioned in the mold 1032 c, such asdepicted in FIG. 10C for example. A substrate substantially similar toany described herein may be placed in the mold cavity 1034 c. Diamondmaterial may be placed in the PCD body cavity 1058 c and the at leastone standing feature recess 1059 c to form a mold assembly. The moldassembly may be placed in a refractory metal container and/or pressuretransmitting medium and the mold assembly may be subjected to HPHTconditions as described herein. The resulting cutting tool may resemble,for example, cutting tool 500 c depicted in FIGS. 5C and 5D.

In some embodiments, at least a portion of the diamond material may beplaced in the mold prior to and/or subsequent to positioning thesubstrate in the mold. For example, a portion of diamond material may bepositioned in the mold in the PCD body cavity 1058 c, then the substratemay then be placed in the mold cavity 1034 c, and last a second portionof diamond material may be positioned in the at least one standingfeature recesses 1059 c. In an embodiment, the diamond material may bepositioned in all recesses prior to insertion of the substrate into themold cavity 1034 c. In an embodiment, the diamond material may bepositioned in the mold 1032 c only after the substrate is positionedtherein. The diamond material may be positioned in the mold 1032 c byusing at least one sprue hole in the mold cavity 1034 c.

In some embodiments, any of the mold cavities of the molds disclosedherein may be coated with a refractory metal foil or refractory paint asdescribed above prior to insertion of a substrate and diamond powdertherein in order to limit contamination of the PCD. The interior of themold need not be coated with a refractory metal when the mold materialwill not affect the quality of or otherwise contaminate the resultingPCD portion or body. For example, when the mold material is HBN, thesubstrate and diamond powder or flute tube may be placed directlyagainst the mold material. Variations of any of the diamond powders, PCDbodies, molds, mold cavities including recesses therein, mold materials,mold forming techniques, substrates including sizes and materials, andother characteristics related to the molding processes, molds andproducts thereof may be used interchangeably between the embodimentsdepicted and/or described herein.

Due to a PCD body containing catalyst material therein, it may exhibitlimited thermal stability and wear resistance at elevated temperaturesinduced during cutting operations. In some embodiments, forming any ofthe tools recited herein may include at least partially leaching thecatalyst material (e.g., cobalt) from the PCD portions of a finishedcutting tool. Such leaching may be accomplished by masking (e.g.,shielding) the substrate such that only the PCD portions being leachedare exposed to the leaching solution, and placing the masked cuttingtool into an leaching solution (e.g., acid bath). Gaseous leaching maybe used in a manner similar to leaching in liquid. Suitable leachingagents include aqua regia, hydrofluoric acid, hydrochloric acid, nitricacid, phosphoric acid, or combinations of the foregoing, in any desiredconcentration. Leaching may be carried out in a pressure vessel.Leaching may be carried out at elevated pressures and/or temperaturesover ambient pressure and temperature. Leaching may be carried out for atime sufficient to leach the PCD portions to a desired depth. Leachingsoak times may be from a few hours to a few weeks or more. Suitable soaktimes, leaching solutions, pressures, and temperatures may be selectedto result in a desired leach depth as measured from the surface of thePCD body therein. Suitable leach depths may be about 100 μm or more,such as about 100 μm to about 2 cm, about 200 μm to about 1 cm, about100 μm to about 800 μm, about 200 μm to about 600 μm, about 200 μm, orabout 400 μm. Any of the cutting tools described herein may exhibitleached PCD portions, and leached PCD portions exhibiting the leachdepths described herein. Leached PCD portions leached to a depth asdescribed herein may have an unleached region nearer the substrate. Theunleached region(s) having catalyst material therein and an at lastpartially leached region nearer the surface of the PCD body. Afterleaching the at least partially leached regions of the PCD portions mayexhibit substantially no catalyst material therein, or may exhibit aresidual amount of catalyst material therein such as about 0.5 weight %to about 5 weight % of catalyst material therein, about 1 weight % toabout 3 weight % of catalyst material therein, about 0.5 weight % toabout 2.5 weight % of catalyst material therein, about 1 weight % ofcatalyst material therein, about 1.5 weight % of catalyst materialtherein. The depth of the at least partially leached and unleachedregions may exhibit thicknesses determined by any combination of leachdepths and standoff distances S described herein. Examples of suitableleaching processes include those described in U.S. Pat. No. 8,596,387issued 3 Dec. 2013; U.S. Provisional Application No. 61/897,764 filed 30Oct. 2013; and U.S. patent application Ser. No. 13/324,237 filed 13 Dec.2011; each of which is incorporated herein by this reference, in itsentirety.

The cutting tools (e.g., PDCs) described herein may be used in a varietyof applications, such as PCD cutting elements on rotary drill bits. FIG.11A is an isometric view and FIG. 11B is a top elevation view of anembodiment of a rotary drill bit 1150. The rotary drill bit 1150includes at least one PCD body, such as a PDC, made or designedaccording to any of the previously described methods. The rotary drillbit 1150 includes a bit body 1152 that includes radially andlongitudinally extending blades 1154 with leading faces 1156, and athreaded pin connection 1158 for connecting the bit body 1152 to adrilling string. The bit body 1152 defines a leading end structure fordrilling into a subterranean formation by rotation about a longitudinalaxis 1160 and application of weight-on-bit. At least one PDC cuttingelement 1100, configured according to any of the previously describedPDCs and PCD cutting tools (e.g., the PDC shown in FIGS. 5C and 5D) maybe affixed to the bit body 1152. With reference to FIG. 11B, each of aplurality of PDC cutting elements 1100 is secured to the blades 1054.For example, each PDC cutting element 1100 may include a PCD body 1106bonded to a substrate 1102, and a plurality of PCD portions 1110 bondedto and extending laterally from the substrate 1102. More generally, thePDC cutting elements 1100 may include any PCD element disclosed herein,without limitation. Also, circumferentially adjacent blades 1154so-called junk slots 1168 are defined therebetween, as known in the art.Additionally, the rotary drill bit 1150 may include a plurality ofnozzle cavities 1170 for communicating drilling fluid from the interiorof the rotary drill bit 1150 to the PDC cutting elements 1000.

FIGS. 11A and 11B merely illustrate one embodiment of a rotary drill bitthat employs at least one PDC cutting element that includes a PCD bodyand substrate configured and fabricated in accordance with the disclosedembodiments, without limitation. The rotary drill bit 1150 is used torepresent any number of earth-boring tools or drilling tools, including,for example, core bits, roller-cone bits, fixed-cutter bits, eccentricbits, bicenter bits, reamers, reamer wings, or any other downhole toolincluding superabrasive compacts, without limitation.

The PCD bodies and PDCs disclosed herein may also be utilized inapplications other than cutting technology. For example, the disclosedPCD bodies and/or PDCs may be used in wire dies, bearings, artificialjoints, inserts, cutting elements, and heat sinks. Thus, any of the PCDbodies disclosed herein may be employed in an article of manufactureincluding at least one superabrasive element or compact.

While various aspects and embodiments have been disclosed herein, otheraspects and embodiments are contemplated. The various aspects andembodiments disclosed herein are for purposes of illustration and arenot intended to be limiting. Additionally, the words “including,”“having,” and variants thereof (e.g., “includes” and “has”) as usedherein, including the claims, shall be open ended and have the samemeaning as the word “comprising” and variants thereof (e.g., “comprise”and “comprises”).

What is claimed is:
 1. A method of making a polycrystalline diamond(“PCD”) structure, the method comprising: forming a mold assembly, themold assembly including: a mold having a cavity therein including atleast one flute recess; a substrate positioned within the cavity, thesubstrate having a surface; and diamond particles positioned within theat least one flute recess; and subjecting the mold assembly to ahigh-pressure/high-temperature (“HPHT”) process effective to sinter thediamond particles and bond at least one PCD portion at least partiallyformed from the diamond particles to an imperforate portion of thesurface of the substrate.